Not only is digital all 0’s and 1’s, those are 0V and 5V steps. These are so far above any possible noise floor of interference that you would have to be sitting next to a electric substation for there to be any possibility of interference pickup. I can build a phono preamp which deals with signals 1/1000th the strength of a USB cable without picking up significant noise. Let me assure you that the engineers who designed USB were well aware of issues of signal degradation and ensured that the standard would be impossible to degrade (quasi balanced transmission for one).
Educate yourself people, there are snake oil salesmen around every corner and the only shield you have is education.
Save your money for where it counts, such as buying an excellent DAC like the Khadas Toneboard. Even my wife can hear the difference over cheaper DAC’s.